61861800 has 384 divisors, whose sum is σ = 259983360. Its totient is φ = 11750400.

The previous prime is 61861781. The next prime is 61861801. The reversal of 61861800 is 816816.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is not an unprimeable number, because it can be changed into a prime (61861801) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 600549 + ... + 600651.

It is an arithmetic number, because the mean of its divisors is an integer number (677040).

Almost surely, 2^61861800 is an apocalyptic number.

61861800 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61861800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (129991680).

61861800 is an abundant number, since it is smaller than the sum of its proper divisors (198121560).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

61861800 is a wasteful number, since it uses less digits than its factorization.

61861800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 153 (or 144 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 30.

The square root of 61861800 is about 7865.2272694436. The cubic root of 61861800 is about 395.4948665933.

It can be divided in two parts, 618 and 61800, that multiplied together give a square (38192400 = 6180²).

The spelling of 61861800 in words is "sixty-one million, eight hundred sixty-one thousand, eight hundred".